More specifically, the invention aims for a heat conduction bus comprising, from a single starting end, a heat-conducting strip provided with a plurality of tabs for solder-connecting to the connection terminals of electronic components likely to become hot, and a collector joined to the strip and arranged so as to channel and evacuate the thermal energy drained by the tabs and passing through the strip.
Such buses are in particular used in the automotive field as “heat sinks” to evacuate the thermal energy supplied by the electronic components of printed circuits.
One of the main obstacles encountered with such buses lies in the fact that, in the soldering operation, it is very difficult to obtain a compromise regarding the parameters of this soldering operation (preheat time and temperature, soldering time, etc.) to ensure a correct soldering for each of the tabs.
In practice, these parameters are the same for all the tabs whereas they should, in an optimal but not practically achievable way, be adapted to each tab to take account of the positioning differences of the latter relative to the collector, which condition the propagation parameters of the thermal energy towards said collector. In practice, when the temperature of a tab located close to the collector is raised, to solder it, it is difficult to bring it quickly to the requisite soldering temperature because the heat is dispersed to the collector and evacuated. This is, moreover, quite normal, since the collector, in normal conditions of use, handles heat evacuation. However, during the soldering of the tabs, it would be desirable for the collector not to provide this heat evacuation function so that the tabs could quickly reach their soldering temperature regardless of their position relative to the collector.
In practice, at the present time, it appears that these difficulties often have the direct consequences of producing soldering conditions (in particular preheat time) that do not make it possible to guarantee a systematic correct soldering of the tabs closest to the collector.
The result of this is that a not-unimportant number of tabs are in fact simply “stuck” to the corresponding connection terminals and not properly soldered to the latter, with the consequential major risks of breaking of the link.